So you think you've got your street killer dialed in just right. You've tried your hand at the stoplight shuffle with the street rats and lived to tell about it, but now it's time you move to the next level: the dragstrip.
If you're like most quarter-mile virgins, you've already convinced yourself that you'll have no problem coming off the line like Warren Johnson. You're in for a shock. Your typical late-model performance car, with its torquey V-8; and stiff, low-profile radial rubber, will prove more difficult to launch than a race-prepped vehicle sporting much more power. And all your practice on the boulevard will seem irrelevant after your first drag launch. It's a traction thing, and you're at a major disadvantage.
We aren't suggesting that you go out and drop a bundle on a set of sticky tires before you drop the hammer, but a little insight will go a long way in making sure you don't sit and spin while your opponent is charging the traps. There is an upside to this situation, however. If you can master the radial launch, you'll be well on your way to effectively piloting stickier, faster cars when the time comes.
Sixty-Foot Times
Measuring how effectively a car transitions from rest to motion is determined by its 60-foot performance. As the term implies, this is the time that elapses from rolling out of the starting beams to breaking the beams 60 feet down the dragstrip. Most racers consider this time to be crucial, particularly in class racing, where the two cars pitted against each other are generally capable of similar trap speeds. In which case, neither vehicle will have the ability to catch the other after a lazy launch.
To put it in perspective, a Top Fuel dragster will run the 60-foot clocks in about 0.75 second; a mid-10-second Camaro or Mustang with stock suspension and slicks will pull around 1.45, and a street-going 12-second Camaro or Mustang on a DOT sticky tire could pull a 1.80. Though a mild street car on radials often pulls well above a 2.2, much better performance is possible with practice and proper technique.
Tire Pressure
One of the novice's most common mistakes is reducing air pressure in street radials in hopes of better bite. This trick worked with bias-ply tires of yore, and it's standard procedure with racing slicks, but radials behave differently. Typically, passenger-car tires are designed to run 3035 psi. Lowering the pressure causes the tire to bulge abnormally at the contact patch and fools many people into believing that the contact patch has actually grown. What really happens is that the tread "cups" at the contact patch, pulling the center of the tire up and off of the pavement and resulting in less traction than would be available at the recommended operating pressure.
If you want more traction than your radials normally provide, then inflate them 5-10 psi more than the factory spec. To determine if your pressure tuning is heading in the right direction, find a dean piece of smooth pavement, and spin the tires across it. An even, dark patch indicates that you're using all of the tire. Dark on the edges and light in the middle means it's underinflated, while dark in the middle means overinflated.
The Burnout
This is another area where classic practices don't apply. Fight the temptation to lay down a tire-shredding, John Force-style burnout. Racing slicks require this kind of preparation, but radials don't. You'll needlessly combust thousands of miles worth of rubber in mere seconds and likely overheat the tires, nulling their bite and exacerbating the traction handicap.
When you pull up to the burnout box, drive around the water. Moving through it can leave water in the tread, which will ultimately run down to the contact patch when you stage. Of course, a big burnout would undoubtedly vaporize the water, but we want to avoid huge smoke shows. All you need to do is "clean" the tires with a small burnout, brushing off pebbles, sand, and other contaminants that might be between the tread and the track surface. On a stick-shift car, simply drop the clutch and spin the tires as you approach the beams; with an automatic, hold the brakes just long enough to start the rubber spinning, and then release the binders and spin the tires to the line. Remember not to go through the staging beams, as you'll likely be disqualified or, at the very least, embarrassed.
Get into the Groove
One of the big differences between track and street is the condition of the surface: not potholes or cracks in the pavement but the amount of rubber on the track and its various characteristics. This varies from track to track, day to day, and hour to hour. To complicate matters, the consistency of the surface will be patterned in longitudinal "grooves" - the tire tracks from previous cars. As a lone wolf (without a crew to walk the track and advise you), you'll have to determine where the best groove is, and line the car up accordingly.
To become truly proficient at this, you'll need experience, but the basics are simple: Find the tracks that are dark and even; avoid bare patches, ripples, and choppy sections. Sometimes, there won't be a groove at all; if possible, walk up to the line and check the surface firsthand before racing.
The Launch
Don't let adrenaline get the best of you. Once you've lighted the first bulb, take a breath and focus. To master the radial launch, you'll need to overcome the temptation to drop the hammer when the lights come down. With a manual transmission, pull into the second set of beams and bring the engine to 2,000 rpm. When the lights come down, drop the clutch, but do not apply the throttle. The car will lunge forward briefly, and just as the nose begins to come back down, lean into the throttle. You'll have to practice this procedure because launch rpm and throttle application will vary depending on the car, the tires, and surrounding circumstances.
For automatics, hold the brake with your left foot and raise rpm with your right one until the engine just begins to load the torque converter. When the lights come down, release the brake, and let the car jump forward before applying more throttle. Again, you'll have to practice to achieve the proper balance between bog and spin.
These guidelines will get you started toward your ultimate goal, with just a touch of tire spin coming out of the hole. Now the only thing between you and sub-2.0 60-foot times is practice.
Source:Hot Rod, Feb 1999 v52 i2 p71(3)
Radial racing: the art of launching on modern street rubber. (drag racing) Terry McGean.
